Merge pull request #10819 from q0w/file404

Author: uranusjr

news/10812.feature.rst

@@ -0,0 +1,2 @@
+Improve error message when ``pip config edit`` is provided an editor that
+doesn't exist.

src/pip/_internal/commands/configuration.py

@@ -225,6 +225,10 @@ def open_in_editor(self, options: Values, args: List[str]) -> None:
 
         try:
             subprocess.check_call([editor, fname])
+        except FileNotFoundError as e:
+            if not e.filename:
+                e.filename = editor
+            raise
         except subprocess.CalledProcessError as e:
             raise PipError(
                 "Editor Subprocess exited with exit code {}".format(e.returncode)

tests/functional/test_configuration.py

@@ -140,3 +140,10 @@ def test_global_config_file(self, script: PipTestEnvironment) -> None:
         global_config_file = get_configuration_files()[kinds.GLOBAL][0]
         result = script.pip("config", "debug")
         assert f"{global_config_file}, exists:" in result.stdout
+
+    def test_editor_does_not_exist(self, script: PipTestEnvironment) -> None:
+        """Ensure that FileNotFoundError sets filename correctly"""
+        result = script.pip(
+            "config", "edit", "--editor", "notrealeditor", expect_error=True
+        )
+        assert "notrealeditor" in result.stderr